In a radio communication system, there are cases where a base station apparatus connects to a plurality of terminal apparatuses. One such a mode of communication where the base station apparatus accesses a plurality of terminal apparatuses is TDMA/TDD. In TDMA/TDD, a frame is constituted by a plurality of time slots, and a plurality of time slots are assigned contiguously. Part of a plurality of time slots contained in each frame is used for uplink, whereas the remaining time slots are used for downlink. In a conventional technology using TDMA/TDD as mentioned above, the number of time slots used for uplink and those used for downlink in each frame are set according to a difference in the traffics (See Patent Document 1, for instance).    [Patent Document 1] Japanese Patent Application Laid-Open No. Hei08-186533.